My dad picked this up in the mid-80's. I don't think it worked then and sure doesn't now. Any schematics or common failures in these? The controller chip might be suspect as a common disk controller problem, so why should the sidecar version be any different? It has voltage, but the +5 is pulled down to 4.87 when connected to the circuit and when it is connected and powered, the -5 line goes a bit more negative compared to its disconnected reading. If that's a clue.
This one is serial 1528133 and LTA0381. So early '81. I know how fragile the thin ribbon wires between the boards are, so I'm reluctant to do my usual disassemble and then give it my best baleful stare.
The drive motor spins at powerup, but no light, head movement or anything other than a console error report. To try it, I just moved the outboard drives' 1&2 cable from my PE box to the sidecar and plugged it into the console port.
I don't have a real use for it, but figure it's worth more working, if it's a fairly simple fix, such as locating and installing a new controller chip, assuming it's not unobtainium.
Thanks in advance!